using System;

public class Program

{

    public static void Main()

    {

        ConvertDate(1730463443208);

        ConvertDate(1730761140000);

        ConvertDate(1730720102000);

        ConvertDate(1730550835437);

    }

​

​

​

    private static void ConvertDate(long unixTimeStamp)

    {

        var dateTimeNowUTC = DateTime.UtcNow;

        var utcOffsetInfo = new DateTimeOffset(dateTimeNowUTC, TimeSpan.Zero);

        var dt = new DateTime(1970, 1, 1, 0, 0, 0, 0).AddSeconds(Math.Round(unixTimeStamp / 1000d)).ToLocalTime();

        Console.WriteLine(dt.ToString());

    }

}